Mold and method for manufacturing the same

Abstract

A method for manufacturing a mold according to the first aspect of the present invention includes the steps of: placing a base material of semiconductor or metal that reacts with sulfur hexafluoride in a reactive ion etching apparatus; supplying a mixed gas of sulfur hexafluoride and oxygen thereto; making the base material undergo a plasma dry-etching process such that oxides are scattered on a surface of the base material, etching advances on the surface of the base material while the oxides function as etching masks, and thereby a fine surface roughness is formed on the surface of the base material; and irradiating the fine surface roughness with an ion beam such that shapes of protrusions of the fine surface roughness can be adjusted.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This is a Continuation of International Patent Application No. PCT / JP2015 / 075073 filed Sep. 3, 2015. The contents of this application is hereby incorporated by reference.BACKGROUNDTechnical Field[0002]The present invention relates to a mold provided with a fine surface roughness thereon, a method for manufacturing the mold and a method for manufacturing a molded product using the mold.Background Art[0003]Anti-reflective structures having a fine surface roughness, the pitch (or the period) of the fine surface roughness being smaller than the wavelength of light, are used in optical elements. As a method for manufacturing molds for such anti-reflective structures, methods in which a resist undergoes patterning using an interference exposure apparatus or an electron-beam lithography system and then etching or electroforming is carried out are known. However, it is difficult to form a fine surface roughness on a large area of a flat surface or...

AI Technical Summary

Benefits of technology

The present invention relates to a method for manufacturing a mold by forming fine surface roughness on a base material using a reactive ion etching process and then adjusting the shape of protrusions on the surface roughness using an ion beam. This method allows for improved anti-reflective feature and provides a smooth surface for the molded products. The resulting mold has good performance and can achieve desired results.

Problems solved by technology

However, it is difficult to form a fine surface roughness on a large area of a flat surface or a curved surface by these methods.

However, when, for example, a fine surface roughness having a pitch of 0.26 micrometers or less that corresponds to the wavelength equal to less than the minimum wavelength of visible lights is formed, it has been difficult to adjust the shape of the fine surface roughness to a sufficient extent by a reactive ion-etching process alone.

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